【摘要】 为研究汽车撞击高速铁路桥墩瞬态撞击力特性,并分析规范设计值的合理性,采用ANSYS LS_DYNA软件建立卡车撞击高速铁路桥墩模型,模拟车辆以60,80,100,120km/h四种速度撞击桥墩的全过程,获得撞击面撞击力时程及峰值,对其动力特性进行分析并和既有研究成果进行比较,计算撞击力的等效静力值并与规范设计值对比分析。结果表明:卡车撞击力呈现为短脉冲荷载形式,持续时间多在0.2s以内;车速越高,撞击作用时间越短,瞬时冲击作用越大,撞击力峰值可达数十MN;撞击力对应的等效静力比我国高速铁路规范和美国AASHTO规范中的撞击力设计值大很多,说明现行规范撞击力设计值偏小,应给予足够重视。更多还原

【Abstract】 To study the characteristics of the instantaneous collision forces of vehicle colliding with the high-speed railway bridge pier and to analyze the rationality of the related designed val- ues in the current codes,the software ANSYS LS_DYNA was used to set up a model for the trucks colliding with the pier and to simulate the whole process of the trucks colliding with the pier at 4kinds of the running speeds of 60,80,100and 120km/h.The time-history curves and peak values of the truck collision forces in the collided surfaces of the pier were obtained,the dy- namic characteristics of the collision forces were analyzed and were compared to the previous re- search findings.The equivalent static force values of the collision forces were calculated and were analytically compared to the designed values in the codes.The results demonstrate that the truck collision forces take the form of short pulse load and mostly the duration time of the load is within 0.2s.The higher the truck running speed is and the shorter the truck collision action is,the greater the instantaneous collision action will be and the peak values of the collision forces can e- ven reach tens of MN.The equivalent static forces corresponding to the collision forces are far greater than the designed values of the collision forces as provided in the Chinese high-speed rail- way code and in the AASHTO,indicating that the designed values in the existing codes are slightly low,to which sufficient attention should be paid.更多还原